High energy electron acceleration with PW-class laser system

We performed electron acceleration experiment with PW‐class laser and a plasma tube, which was created by imploding a hollow polystyrene cylinder. In this experiment, electron energies in excess of 600 MeV have been observed. Moreover, the spectra of a comparatively high‐density plasma ∼1019 cm−3 had a bump around 10 MeV. Additionally, we performed the absolute sensitivity calibration of imaging plate for 1 GeV electrons from the injector Linac of Spring‐8 in order to evaluate absolute number of GeV‐class electrons in the laser acceleration experiment.